Normative Values of Echocardiographic Chamber Size and Function in Older Healthy Adults: The Multi-Ethnic Study of Atherosclerosis.

BACKGROUND: Echocardiographic (2-dimensional echocardiography) thresholds indicating disease or impaired functional status compared with normal physiological aging in individuals aged ≥65 years are not clearly defined. In the present study, we sought to establish standard values for 2-dimensional echocardiography parameters related to chamber size and function in older adults without cardiopulmonary or cardiometabolic conditions. METHODS: In this cross-sectional study of 3032 individuals who underwent 2-dimensional echocardiography at exam 6 in the MESA (Multi-Ethnic Study of Atherosclerosis), 608 participants fulfilled our inclusion criteria of healthy aging, with normative values defined as the mean ± 1.96 standard deviation and compared across sex and race and ethnicity. Functional status measures included NT-proBNP (N-terminal pro-B-type natriuretic peptide), 6-minute walk distance, and Kansas City Cardiomyopathy Questionnaire. Prognostic performance using MESA cutoffs was compared with established guideline cutoffs using time-to-event analysis. RESULTS: The normative aging cohort (69.5±7.0 years, 46.2% male, 47.5% White) had lower NT-proBNP, higher 6-minute walk distance, and higher (better) Kansas City Cardiomyopathy Questionnaire summary values. Women had significantly smaller chamber sizes and better biventricular systolic function. White participants had the largest chamber dimensions, whereas Chinese participants had the smallest, even after adjustment for body size. Current guidelines identified 81.6% of healthy older adults in MESA as having cardiac abnormalities. CONCLUSIONS: Among a large, diverse group of healthy older adults, we found significant differences in cardiac structure and function by sex and race/ethnicity, which may signal sex-specific cardiac remodeling with advancing age. It is crucial for existing guidelines to consider the observed and clinically significant differences in cardiac structure and function associated with healthy aging. Our study highlights that existing guidelines, which grade abnormalities in echocardiographic cardiac chamber size and function based on younger individuals, may not adequately address the anticipated changes associated with normal aging.

TRIGLYCERIDE - GLUCOSE INDEX, REMNANT CHOLESTEROL AND COMMON CAROTID ARTERY INTIMA-MEDIA THICKNESS AS AN ATHEROSCLEROTIC MARKER IN ISCHEMIC STROKE PATIENTS.

Ischemic stroke (IS) is a major global health concern, often resulting from atherosclerosis and insulin resistance (IR). The triglyceride-glucose index (TyG index), remnant cholesterol (RC), and common artery intima-media thickness (CIMT) are potential markers for assessing atherosclerosis and cardiovascular risk in IS patients. A cross-sectional study was conducted to investigate the association between TyG index, RC, CIMT, and IS in adult patients recruited from a hospital. Demographic, clinical, and laboratory data were collected, and statistical analysis was performed. The study included 50 participants with a balanced gender distribution and a mean age of 57.64 years. Laboratory characteristics showed notable values, and CIMT > 0.6 mm was associated with higher NIH Stroke Scale scores. RC exhibited significant correlations with age, CIMT, lipid profile, and TyG index. The study highlights the potential of TyG index, RC, and CIMT as atherosclerotic markers in IS patients. Favorable prognostic outcomes were observed, emphasizing the importance of early diagnosis and management to improve patient outcomes.

Reference Values for Indexed Echocardiographic Chamber Sizes in Older Adults: The Multi-Ethnic Study of Atherosclerosis.

BACKGROUND: Normalization of echocardiographic chamber measurements for body surface area may result in misclassification of individuals with obesity or sarcopenia. Normalization for alternative measures of body size may be preferable, but there remains a dearth of information on their normative values and association with cardiovascular function metrics. METHODS AND RESULTS: A total of 3032 individuals underwent comprehensive 2-dimensional echocardiography at Exam 6 in MESA (Multi-Ethnic Study of Atherosclerosis). In the subgroup of 608 individuals free of cardiopulmonary disease (69.5±7.0 years, 46% male, 48% White, 17% Chinese, 15% Black, 21% Hispanic), normative values were derived for left and right cardiac chamber measurements across a variety of ratiometric (body surface area, body mass index, height) and allometric (height1.6, height2.7) scaling parameters. Normative upper and lower reference values were provided for each scaling parameter stratified across age groups, sex, and race or ethnicity. Among scaling parameters, body surface area and height were associated with the least variability across race and ethnicity categories and height2.7 was associated with the least variability across sex categories. CONCLUSIONS: In this diverse cohort of community-dwelling older adults, we provide normative values for common echocardiographic parameters across a variety of indexation methods.

Detection of subclinical atherosclerosis using vascular ultrasound as a vascular risk assessment method. Simplified protocol. / Detección de aterosclerosis subclínica mediante ecografía vascular como método de evaluación de riesgo vascular. Protocolo simplificado.

Cardiovascular disease secondary to atherosclerosis is the main cause of morbidity and mortality in the world. Cardiovascular risk stratification has proven to be an insufficient approach to detect those subjects who are going to suffer a cardiovascular event, which is why for years other markers have been sought to help stratify each individual with greater precision. Two-dimensional vascular ultrasound is a excellent method for vascular risk assessment.

Ros-responsive nano-platform for lipid-specific fluorescence imaging of atherosclerosis.

Fluorescent probes that specifically targeting Lipid droplets (LDs) have shown potential in biological imaging. Albeit, their in vivo applications are limited due to the hydrophobicity, low signal-to-noise ratio (SNR) and LDs-specificity. Thus, we designed a novel probe namely MeOND, and a reactive oxygen species (ROS)-responsive nano-platform to improve in vivo LDs-specific imaging. MeOND exhibits a remarkable twisted intramolecular charge transfer (TICT) effect with a strongly enhanced near-infrared emission in low-polarity lipid environment. Also, MeOND demonstrates satisfactory biocompatibility and superior intracellular LDs imaging capabilities. MeOND encapsulated nano-platform (MeOND@PMM) presented favorable water solubility and biocompatibility. MeOND@PMM remains stable in physiological conditions but quickly degrades in the environment of elevated ROS level. The released MeOND could then light up the intracellular LDs in atherosclerotic plaques. The design of the probe and nano-platform is expected to provide a better tool for the scientific research of LDs and LDs-related diseases.

Multiparameter Assessment of Foam Cell Formation Progression Using a Dual-Color Switchable Fluorescence Probe.

The assessment of atherosclerosis (AS) progression has emerged as a prominent area of research. Monitoring various pathological features of foam cell (FC) formation is imperative to comprehensively assess AS progression. Herein, a simple benzospiropyran-julolidine-based probe, BSJD, with switchable dual-color imaging ability was developed. This probe can dynamically and reversibly adjust its molecular structure and fluorescent properties in different polar and pH environments. Such a polarity and pH dual-responsive characteristic makes it superior to single-responsive probes in dual-color imaging of lipid droplets (LDs) and lysosomes as well as monitoring their interaction. By simultaneously tracking various pathological features, including LD accumulation and size changes, lysosome dysfunction, and dynamically regulated lipophagy, more comprehensive information can be obtained for multiparameter assessment of FC formation progression. Using BSJD, not only the activation of lipophagy in the early stages and inhibition in the later phases during FC formation are clearly observed but also the important roles of lipophagy in regulating lipid metabolism and alleviating FC formation are demonstrated. Furthermore, BSJD is demonstrated to be capable of rapidly imaging FC plaque sites in AS mice with fast pharmacokinetics. Altogether, BSJD holds great promise as a dual-color organelle-imaging tool for investigating disease-related LD and lysosome changes and their interactions.

In Vivo Fluorescent Labeling of Foam Cell-Derived Extracellular Vesicles as Circulating Biomarkers for In Vitro Detection of Atherosclerosis.

Real-time monitoring of the development of atherosclerosis (AS) is key to the management of cardiovascular disease (CVD). However, existing laboratory approaches lack sensitivity and specificity, mostly due to the dearth of reliable AS biomarkers. Herein, we developed an in vivo fluorescent labeling strategy that allows specific staining of the foam cell-derived extracellular vesicles (EVs) in atherosclerotic plaques, which are released into the blood as circulating biomarkers for in vitro detection of AS. This strategy relies on a self-assembled nanoprobe that could recognize foam cells specifically, where the probe is degraded by the intracellular HClO to produce a trifluoromethyl-bearing boron-dipyrromethene fluorophore (termed B-CF3), a lipophilic dye that can be transferred to the exosomal membranes. These circulating B-CF3-stained EVs can be detected directly on a fluorescence spectrometer or microplate reader without resorting to any sophisticated analytical method. This liquid-biopsy format enables early detection and real-time differentiation of lesion vulnerability during AS progression, facilitating effective CVD management.

Atherosclerosis and depression: is carotid intima-media thicker in patients with depression compared to matched control individuals? A systematic review and meta-analysis.

OBJECTIVE: To investigate if there is an association between atherosclerosis and depression by using as imaging biomarker the carotid intima media thickness (cIMT), a surrogate marker for atherosclerosis. METHODS: PubMed/Medline, Embase and Cochrane databases were comprehensively searched to identify studies investigating the association between cIMT and depression. The results were pooled using a random-effects statistical model, appropriate for the expected high heterogeneity. Sensitivity and subgroup analyses were conducted where data was available. RESULTS: Overall, 22 and 13 studies met inclusion criteria for the qualitative and the quantitative synthesis, respectively, with a total of 4466 patients and 21,635 control participants. Results showed that cIMT is significantly higher in the depression, compared to the control groups with an overall mean difference of 0.07 mm (95% CI 0.04-0.10, p < 0.01). Subgroup analysis showed that diabetes could present as a confounding factor in patients with depression and an increased cIMT. CONCLUSIONS: This study confirms a significantly increased cIMT in patients with depression, compared with controls and suggests a possible bidirectional link between atherosclerosis and depression. An early screening of cardiovascular disease in individuals suffering with depression should be considered.

Establishment of a hybrid model of atherosclerosis and acute colitis in ApoE-/- mice.

Inflammatory bowel disease (IBD) and atherosclerosis (AS) are both common chronic inflammatory diseases with similar pathophysiological mechanisms. Some studies have shown that IBD patients are at increased risk for early atherosclerosis, myocardial infarction and venous thrombosis. Here we set up a hybrid mouse model associated with atherosclerosis and acute colitis in order to investigate the interplay of the two diseases. We fed ApoE-/- mice with high fat diet to establish atherosclerosis model, and used animal ultrasound machine to detect the artery of mice noninvasively. Then a new hybrid model of atherosclerosis and acute colitis was prepared by drinking water for 7 days. At the end of the experiment, the hybrid model mice showed typically pathological and intuitionistic changes of atherosclerosis and acute colitis. We found the shortened colon length, high histopathological scores of the colon with mucosal erosion and necrosis, hyperlipidemia, a plaque-covered mouse aorta and plaque with foam cells and lipid deposition in the hybrid model group, which proved that the hybrid model was successfully established. At the same time, ultrasonic detection showed that the end-diastolic blood flow velocity and the relative dilation value were decreased, while systolic time / diastolic time, the wall thickness, systolic diameters as well as diastolic diameters were gradually increased, and statistical significance appeared as early as 8 weeks. We clearly described the process of establishing a hybrid model of atherosclerosis and acute colitis, which might provide a repeatable platform for the interaction mechanism exploring and drug screening of atherosclerosis and inflammatory bowel disease in preclinical study.

Sphingomyelinase-responsive nanomicelles for targeting atherosclerosis.

Atherosclerosis, a leading cause of cardiovascular diseases requires approaches to enhance disease monitoring and treatment. Nanoparticles offer promising potential in this area by being customisable to target components or molecular processes within plaques, while carrying diagnostic and therapeutic agents. However, the number of biomarkers available to target this disease is limited. This study investigated the use of sphingomyelin-based nanomicelles triggered by sphingomyelinase (SMase) in atherosclerotic plaques. Accumulation of iron oxide-based nanomicelles in the plaque was demonstrated by fluorescence, MR imaging and electron microscopy. These findings demonstrate the possibility of utilising SMase as a mechanism to retain nanoprobes within plaques, thus opening up possibilities for future therapeutic interventions.

3-D transesophageal echocardiography aids in assessment of embolic stroke due to aortic atherosclerotic plaque: A case series.

Atherosclerosis is the most common cause of heart disease and stroke. Plaque thickness ≥4 mm in the ascending aorta or aortic arch is strongly correlated with cerebral embolic events and ischemic stroke. However, despite imaging workup, the cause of embolic stroke remains unidentified in many patients. Transesophageal echocardiography (TEE) is the preferred echocardiographic method for the evaluation of cardiac source of emboli. 2D TEE imaging evaluates aortic root and aortic arch in a single plane or two planes with biplane imaging. However, 2D TEE often fails to detect mobile or complex components in the ascending aorta and aortic arch plaques. The routine availability of 3D TEE in current ultrasound systems may significantly improve the assessment of aortic plaques as a potential embolic source. In this case series, we present four consecutive patients with stroke who underwent TEE by a single cardiologist for possible cardioembolic source. Some of these patients may have been labelled as "cryptogenic stroke" or "embolic stroke of undetermined source" (ESUS) due to the presence of insignificant or nonmobile ascending aortic or aortic arch plaques on 2D TEE imaging. In our four consecutive patients with ESUS who underwent TEE by a single operator, 3D TEE showed complex aortic arch plaques with ulceration with mobile components and established these plaques as the likely source of embolic stroke.

Relation between non-alcoholic fatty liver disease and carotid artery intimal media thickness as a surrogate for atherosclerosis: a systematic review and meta-analysis.

BACKGROUND AND OBJECTIVE: Non-alcoholic fatty liver disease (NAFLD), characterized by hepatic steatosis without heavy alcohol consumption or other chronic conditions, encompasses a spectrum from non-alcoholic fatty liver to non-alcoholic steatohepatitis leading to cirrhosis. This analysis aimed to investigate the correlation between NAFLD and carotid intimal media thickness (C-IMT), a non-invasive surrogate for atherosclerosis. METHODOLOGY: Database searches, including PubMed, EMBASE and Cochrane Library, yielded studies up to April 2023. Included were studies exploring the NAFLD-C-IMT relationship in populations aged >18 years. Exclusions comprised non-English papers, those involving animals or pediatric populations and studies lacking control groups. RESULTS: No statistical significance was noted between mild and moderate NAFLD compared to the control group regarding C-IMT [95% confidence intervals (CI): -0.03, 0.12] and (95% CI: -0.03, 0.21), respectively. There was a statistically significant difference only in the Severe NAFLD group ( P value 0.03). NAFLD with and without metabolic syndrome showed statistically significant differences compared to control regarding C-IMT (95% CI: 0.04, 0.12) and (95% CI: 0.01, 0.07), respectively. Fifty-nine studies were mentioned without classification of NAFLD severity and revealed a high statistically significant difference between NAFLD and controls regarding C-IMT with (95% CI: 0.09, 0.12, P < 0.00001). Stratified analysis according to sex was done in two studies and revealed statistical differences between NAFLD and control regarding C-IMT in both groups. CONCLUSION: This meta-analysis underscores a significant association between NAFLD and increased C-IMT, emphasizing the importance of assessing C-IMT in NAFLD patients to identify cardiovascular risk and tailor therapeutic interventions for improved patient outcomes.

Associations between 3D-based Left Atrial Volumetric and Blood Flow Parameters in a Single-Site Cohort of the Multi-Ethnic Study of Atherosclerosis.

Purpose To investigate associations between left atrial volume (LAV) and function with impaired three-dimensional hemodynamics from four-dimensional flow MRI. Materials and Methods A subcohort of participants from the Multi-Ethnic Study of Atherosclerosis from Northwestern University underwent prospective 1.5-T cardiac MRI including whole-heart four-dimensional flow and short-axis cine imaging between 2019 and 2020. Four-dimensional flow MRI analysis included manual three-dimensional segmentations of the LA and LA appendage (LAA), which were used to quantify LA and LAA peak velocity and blood stasis (% voxels < 0.1 m/sec). Short-axis cine data were used to delineate LA contours on all cardiac time points, and the resulting three-dimensional-based LAVs were extracted for calculation of LA emptying fractions (LAEFtotal, LAEFactive, LAEFpassive). Stepwise multivariable linear models were calculated for each flow parameter (LA stasis, LA peak velocity, LAA stasis, LAA peak velocity) to determine associations with LAV and LAEF. Results This study included 158 participants (mean age, 73 years ± 7 [SD]; 83 [52.5%] female and 75 [47.4%] male participants). In multivariable models, a 1-unit increase of LAEFtotal was associated with decreased LA stasis (ß coefficient, -0.47%; P < .001), while increased LAEFactive was associated with increased LA peak velocity (ß coefficient, 0.21 cm/sec; P < .001). Furthermore, increased minimum LAV indexed was most associated with impaired LAA flow (higher LAA stasis [ß coefficient, 0.65%; P < .001] and lower LAA peak velocity [ß coefficient, -0.35 cm/sec; P < .001]). Conclusion Higher minimum LAV and reduced LA function were associated with impaired flow characteristics in the LA and LAA. LAV assessment might therefore be a surrogate measure for LA and LAA flow abnormalities. Keywords: Atherosclerosis, Left Atrial Volume, Left Atrial Blood Flow, 4D Flow MRI Supplemental material is available for this article. © RSNA, 2024.

Development of a CD163-Targeted PET Radiotracer That Images Resident Macrophages in Atherosclerosis.

Tissue-resident macrophages are complementary to proinflammatory macrophages to promote the progression of atherosclerosis. The noninvasive detection of their presence and dynamic variation will be important to the understanding of their role in the pathogenesis of atherosclerosis. The goal of this study was to develop a targeted PET radiotracer for imaging CD163-positive (CD163+) macrophages in multiple mouse atherosclerosis models and assess the potential of CD163 as a biomarker for atherosclerosis in humans. Methods: CD163-binding peptide was identified using phage display and conjugated with a NODAGA chelator for 64Cu radiolabeling ([64Cu]Cu-ICT-01). CD163-overexpressing U87 cells were used to measure the binding affinity of [64Cu]Cu-ICT-01. Biodistribution studies were performed on wild-type C57BL/6 mice at multiple time points after tail vein injection. The sensitivity and specificity of [64Cu]Cu-ICT-01 in imaging CD163+ macrophages upregulated on the surface of atherosclerotic plaques were assessed in multiple mouse atherosclerosis models. Immunostaining, flow cytometry, and single-cell RNA sequencing were performed to characterize the expression of CD163 on tissue-resident macrophages. Human carotid atherosclerotic plaques were used to measure the expression of CD163+ resident macrophages and test the binding specificity of [64Cu]Cu-ICT-01. Results: [64Cu]Cu-ICT-01 showed high binding affinity to U87 cells. The biodistribution study showed rapid blood and renal clearance with low retention in all major organs at 1, 2, and 4 h after injection. In an ApoE-/- mouse model, [64Cu]Cu-ICT-01 demonstrated sensitive and specific detection of CD163+ macrophages and capability for tracking the progression of atherosclerotic lesions; these findings were further confirmed in Ldlr-/- and PCSK9 mouse models. Immunostaining showed elevated expression of CD163+ macrophages across the plaques. Flow cytometry and single-cell RNA sequencing confirmed the specific expression of CD163 on tissue-resident macrophages. Human tissue characterization demonstrated high expression of CD163+ macrophages on atherosclerotic lesions, and ex vivo autoradiography revealed specific binding of [64Cu]Cu-ICT-01 to human CD163. Conclusion: This work reported the development of a PET radiotracer binding CD163+ macrophages. The elevated expression of CD163+ resident macrophages on human plaques indicated the potential of CD163 as a biomarker for vulnerable plaques. The sensitivity and specificity of [64Cu]Cu-ICT-01 in imaging CD163+ macrophages warrant further investigation in translational settings.

Role of 18F-sodium fluoride positron emission tomography in imaging atherosclerosis.

Atherosclerosis involving vascular beds across the human body remains the leading cause of death worldwide. Coronary and peripheral artery disease, which are almost universally a result of atherosclerotic plaque, can manifest clinically as myocardial infarctions, ischemic stroke, or acute lower-limb ischemia. Beyond imaging myocardial perfusion and blood-flow, nuclear imaging has the potential to depict the activity of the processes that are directly implicated in the atherosclerotic plaque progression and rupture. Out of several tested tracers to date, the literature is most advanced for 18F-sodium fluoride positron emission tomography. In this review, we present the latest data in the field of atherosclerotic 18F-sodium fluoride positron emission tomography imaging, discuss the advantages and limitation of the techniques, and highlight the aspects that require further research in the future.

Accumulation of Iron Oxide-Based Contrast Agents in Rabbit Atherosclerotic Plaques in Relation to Plaque Age and Vulnerability Features.

Purpose: In this study, a detailed characterization of a rabbit model of atherosclerosis was performed to assess the optimal time frame for evaluating plaque vulnerability using superparamagnetic iron oxide nanoparticle (SPION)-enhanced magnetic resonance imaging (MRI). Methods: The progression of atherosclerosis induced by ballooning and a high-cholesterol diet was monitored using angiography, and the resulting plaques were characterized using immunohistochemistry and histology. Morphometric analyses were performed to evaluate plaque size and vulnerability features. The accumulation of SPIONs (novel dextran-coated SPIONDex and ferumoxytol) in atherosclerotic plaques was investigated by histology and MRI and correlated with plaque age and vulnerability. Toxicity of SPIONDex was evaluated in rats. Results: Weak positive correlations were detected between plaque age and intima thickness, and total macrophage load. A strong negative correlation was observed between the minimum fibrous cap thickness and plaque age as well as the mean macrophage load. The accumulation of SPION in the atherosclerotic plaques was detected by MRI 24 h after administration and was subsequently confirmed by Prussian blue staining of histological specimens. Positive correlations between Prussian blue signal in atherosclerotic plaques, plaque age, and macrophage load were detected. Very little iron was observed in the histological sections of the heart and kidney, whereas strong staining of SPIONDex and ferumoxytol was detected in the spleen and liver. In contrast to ferumoxytol, SPIONDex administration in rabbits was well tolerated without inducing hypersensitivity. The maximum tolerated dose in rat model was higher than 100 mg Fe/kg. Conclusion: Older atherosclerotic plaques with vulnerable features in rabbits are a useful tool for investigating iron oxide-based contrast agents for MRI. Based on the experimental data, SPIONDex particles constitute a promising candidate for further clinical translation as a safe formulation that offers the possibility of repeated administration free from the risks associated with other types of magnetic contrast agents.

Progression of subclinical atherosclerosis in ankylosing spondylitis: a 10-year prospective study.

Chronic systemic inflammation contributes to increased CVD burden in Ankylosing Spondylitis (AS). Since long-term follow-up data on subclinical atherosclerosis acceleration are lacking, we examined its progression in contemporary AS patients during 10 years. Fifty-three (89% male, aged 50.4 (36.3-55.9) years,) non-diabetic, CVD-free AS patients and 53 age-sex-matched non-diabetic, control individuals were re-evaluated after 9.2-10.2 years by ultrasonography for carotid/femoral atheromatosis, pulse wave velocity (PWV) and intima-media thickness (IMT), performed by the same operator/protocol. New atheromatic plaque formation, PWV deterioration, and IMT increase were associated only with classical CVD risk factors, as reflected by the heartSCORE (age, gender, smoking status, blood pressure and cholesterol levels) by multivariate analysis, rather than disease presence. However, among AS patients, despite remission/low disease activity at follow-up end in 79%, atheromatosis progression was associated by multivariate analysis with higher BASDAI scores (p = 0.028), independently of biologic therapies administered in 2/3 of them. Moreover, in AS patients, but not in controls, PWV values at baseline were associated with plaque progression during the 10-year follow-up after taking into account baseline heartSCORE and plaque burden status (p = 0.033). Despite comparable prevalence of both hypertension and hypercholesterolemia at baseline between patients and controls, a lower percentage of AS patients had achieved "adequate" CVD risk factor control at follow-up end (11% vs 25% respectively, p = 0.076). Classical CVD risk factors and residual disease activity account for the progression of subclinical atherosclerosis in AS, pointing to the unmet needs in the contemporary management of these patients.

On the Impact of Residual Strains in the Stress Analysis of Patient-Specific Atherosclerotic Carotid Vessels: Predictions Based on the Homogenous Stress Hypothesis.

The identification of carotid atherosclerotic lesion at risk for plaque rupture, eventually resulting in cerebral embolism and stroke, is of paramount clinical importance. High stress in the fibrous plaque cap has been proposed as risk factor. However, among others, residual strains influence said stress predictions, but quantitative and qualitative implications of residual strains in this context are not well explored. We therefore propose a multiplicative kinematics-based Growth and Remodeling (G&R) framework to predict residual strains from homogenizing tissue stress and then investigate its implication on plaque stress. Carotid vessel morphology of four patients was reconstructed from clinical Computed Tomography-Angiography (CT-A) images and equipped with heterogeneous tissue constitutive properties assigned through a histology-based artificial intelligence image segmentation tool. As compared to a purely elastic analysis and depending on patient-specific morphology and tissue distributions, the incorporation of residual strains reduced the maximum wall stress by up to 30 % and resulted in a fundamentally different distribution of stress across the atherosclerotic wall. Regardless residual strains homogenized tissue stresses, the fibrous plaque cap may persistently be exposed to spots of high stress. In conclusion, the incorporation of residual strains in biomechanical studies of atherosclerotic carotids may be important for a reliable assessment of fibrous plaque cap stress.

Associations Between Mid-Life Psychosocial Measures and Estimated Late Life Amyloid Burden: The Atherosclerosis Risk in Communities (ARIC)-PET Study.

Background: Psychosocial factors are modifiable risk factors for Alzheimer's disease (AD). One mechanism linking psychosocial factors to AD risk may be through biological measures of brain amyloid; however, this association has not been widely studied. Objective: To determine if mid-life measures of social support and social isolation in the Atherosclerosis Risk in Communities (ARIC) Study cohort are associated with late life brain amyloid burden, measured using florbetapir positron emission tomography (PET). Methods: Measures of social support and social isolation were assessed in ARIC participants (visit 2: 1990-1992). Brain amyloid was evaluated with florbetapir PET standardized uptake value ratios (SUVRs; visit 5: 2012-2014). Results: Among 316 participants without dementia, participants with intermediate (odds ratio (OR), 0.47; 95% CI, 0.25-0.88), or low social support (OR, 0.43; 95% CI, 0.22-0.83) in mid-life were less likely to have elevated amyloid SUVRs, relative to participants with high social support. Participants with moderate risk for social isolation in mid-life (OR, 0.32; 95% CI, 0.14-0.74) were less likely to have elevated amyloid burden than participants at low risk for social isolation. These associations were not significantly modified by sex or race. Conclusions: Lower social support and moderate risk of social isolation in mid-life were associated with lower odds of elevated amyloid SUVR in late life, compared to participants with greater mid-life psychosocial measures. Future longitudinal studies evaluating mid-life psychosocial factors, in relation to brain amyloid as well as other health outcomes, will strengthen our understanding of the role of these factors throughout the lifetime.

Modic Changes in the Lumbar Spine: Exploring Their Association with Abdominal Aortic Calcification as a Potential Indicator of Systemic Atherosclerosis.

BACKGROUND: This was a cross-sectional study on the correlation between abdominal aortic calcification (AAC) and Modic changes (MC). Little is known regarding the etiology of MC in the lumbar spine. Currently, insufficient vascularization of the endplate has been proposed to contribute to the appearance of MC. Our objective was to investigate whether AAC, a marker for a poor vascular status, is associated with MC in patients suffering from degenerative disc disease. METHODS: Radiologic images of patients (n = 130) suffering from degenerative lumbar disc disease were reviewed. Type and severity of MC were assessed using magnetic resonance images, and severity of AAC was evaluated using computed tomography images or fluoroscopy. Both items were dichotomized into minimal and relevant grades. The correlation between them was studied using Spearman's correlation test, with age as a covariate. RESULTS: Of the patients, 113 (87%) demonstrated MC (31% type I, 63% type II, and 6% type III) (55% relevant grade), and 68% had AAC (44% relevant grade). Spearman statistical analysis revealed that AAC was correlated with age (P < 0.001), whereas MC were not (P = 0.142). AAC severity was significantly correlated with MC, remaining so after age adjustment (P < 0.05). While MC type I lacked correlation with AAC, MC type II were significantly correlated with AAC (0.288, P = 0.015); however, this association lost significance after adjusting for age (P = 0.057). CONCLUSIONS: AAC and MC (mainly MC type II) are associated, indicating that reduced blood supply or even a poor systemic vascularization status due to atherosclerotic disease may play a role in the formation of MC. Future studies focusing on the etiology of MC should pay more attention to patients' vascular status and determinants of abdominal aorta calcification.